Compositions for treating cmt and related disorders

ABSTRACT

The present invention relates to compositions and methods for the treatment of the Charcot-Marie-Tooth disease and related disorders.

The present invention relates to compositions and methods for thetreatment of the Charcot-Marie-Tooth disease and related disorders.

Charcot-Marie-Tooth disease (“CMT”) is an orphan genetic peripheral polyneuropathy. Affecting approximately 1 in 2,500 individuals, this diseaseis the most common inherited disorder of the peripheral nervous system.Its onset typically occurs during the first or second decade of life,although it may be detected in infancy. Course of disease is chronicwith gradual neuromuscular degeneration. The disease is invalidatingwith cases of accompanying neurological pain and extreme musculardisability. CMT is one of the best studied genetic pathologies withapproximately 30,000 cases in France. While a majority of CMT patientsharbour a duplication of a chromosome 17 fragment containing a myelingene: PMP22 (form CMT1A), two dozens of genes have been implicated indifferent forms of CMT. Accordingly, although monogenic in origin, thispathology manifests clinical heterogeneity due to possible modulatorgenes. The genes mutated in CMT patients are clustering around tightlyconnected molecular pathways affecting differentiation of Schwann cellsor neurons or changing interplay of these cells in peripheral nerves.

Mining of publicly available data, describing molecular mechanisms andpathological manifestations of the CMT1A disease, allowed us toprioritize a few functional cellular modules—transcriptional regulationof PMP22 gene, PMP22 protein folding/degradation, Schwann cellproliferation and apoptosis, death of neurons, extra-cellular matrixdeposition and remodelling, immune response—as potential legitimatetargets for CMT-relevant therapeutic interventions. The combined impactof these deregulated functional modules on onset and progression ofpathological manifestations of Charcot-Marie-Tooth justifies a potentialefficacy of combinatorial CMT treatment.

International patent application no PCT/EP2008/066457 describes a methodof identifying drug candidates for the treatment of theCharcot-Marie-Tooth disease by building a dynamic model of the pathologyand targeting functional cellular pathways which are relevant in theregulation of CMT disease.

International patent application no PCT/EP2008/066468 describescompositions for the treatment of the Charcot-Marie-Tooth disease whichcomprise at least two compounds selected from the group of multiple drugcandidates.

SUMMARY OF INVENTION

The purpose of the present invention is to provide new therapeuticcombinations for treating CMT and related disorders. The invention thusrelates to compositions and methods for treating CMT and relateddisorders, in particular toxic neuropathy and amyotrophic lateralsclerosis, using particular drug combinations.

An object of this invention more specifically relates to a compositioncomprising Baclofen, Sorbitol and a compound selected from Pilocarpine,Methimazole, Mifepristone, Naltrexone, Rapamycine, Flurbiprofen andKetoprofen, salts or prodrugs thereof, for simultaneous, separate orsequential administration to a mammalian subject.

A particular object of the present invention relates to a compositioncomprising Baclofen, Sorbitol and Naltrexone, for simultaneous, separateor sequential administration to a mammalian subject.

Another object of the invention relates to a composition comprising (a)rapamycin, (b) mifepristone or naltrexone, and (c) a PMP22 modulator,for simultaneous, separate or sequential administration to a mammaliansubject.

In a particular embodiment, the PMP22 modulator is selected fromAcetazolamide, Albuterol, Amiloride, Aminoglutethimide, Amiodarone,Aztreonam, Baclofen, Balsalazide, Betaine, Bethanechol, Bicalutamide,Bromocriptine, Bumetanide, Buspirone, Carbachol, Carbamazepine,Carbimazole, Cevimeline, Ciprofloxacin, Clonidine, Curcumin,Cyclosporine A, Diazepam, Diclofenac, Dinoprostone, Disulfiram,D-Sorbitol, Dutasteride, Estradiol, Exemestane, Felbamate, Fenofibrate,Finasteride, Flumazenil, Flunitrazepam, Flurbiprofen, Furosemide,Gabapentin, Galantamine, Haloperidol, Ibuprofen, Isoproterenol,Ketoconazole, Ketoprofen, L-carnitine, Liothyronine (T3), Lithium,Losartan, Loxapine, Meloxicam, Metaproterenol, Metaraminol, Metformin,Methacholine, Methimazole, Methylergonovine, Metoprolol, Metyrapone,Miconazole, Mifepristone, Nadolol, Naloxone, Naltrexone; Norfloxacin,Pentazocine, Phenoxybenzamine, Phenylbutyrate, Pilocarpine,Pioglitazone, Prazosin, Propylthiouracil, Raloxifene, Rapamycin,Rifampin, Simvastatin, Spironolactone, Tacrolimus, Tamoxifen, Trehalose,Trilostane, Valproic acid, salts or prodrugs thereof.

Another object of this invention is a composition comprising Rapamycinand mifepristone, for simultaneous, separate or sequentialadministration to a mammalian subject.

A further object of this invention is a composition as disclosed abovefurther comprising one or several pharmaceutically acceptable excipientsor carriers (i.e., a pharmaceutical composition).

Another object of the present invention relates to a composition asdisclosed above for treating CMT or a related disorder.

A further object of this invention relates to the use of a combinationof compounds as disclosed above for the manufacture of a medicament forthe treatment of CMT or a related disorder.

A further object of this invention is a method for treating CMT or arelated disorder, the method comprising administering to a subject inneed thereof an effective amount of a composition as defined above.

A further object of this invention is a method of preparing apharmaceutical composition, the method comprising mixing the abovecompounds in an appropriate excipient or carrier.

A more specific object of this invention is a method of treating CMT1ain a subject, the method comprising administering to the subject in needthereof an effective amount of a compound or combination of compounds asdisclosed above.

A further specific object of this invention is a method of treatingtoxic neuropathy in a subject, the method comprising administering tothe subject in need thereof an effective amount of a compound orcombination of compounds as disclosed above.

A further specific object of this invention is a method of treating ALSin a subject, the method comprising administering to the subject in needthereof an effective amount of a compound or combination of compounds asdisclosed above.

Any of the various uses or methods of treatment disclosed herein canalso include an optional step of diagnosing a patient as having CMT or arelated disorder, particularly CMT1A, or identifying an individual as atrisk of developing CMT or a related disorder, particularly CMT1A.

In this regard, a further object of this invention is a method oftreating CMT, particularly CMT1a, the method comprising (1) assessingwhether a subject has CMT, particularly CMT1a and (2) treating thesubject having CMT, particularly CMT1a with an effective amount of acombination of compounds as described above. Determining whether asubject has CMT, particularly CMT1a, can be done by various tests knownper se in the art, such as DNA assays.

The invention may be used for treating CMT or a related disorder in anymammalian subject, particularly human subjects, more preferably CMT1a.

LEGEND TO THE FIGURES

FIG. 1. Synergistic effect of drug combination, dose 1: effect of A)Mix7 (dose 1, day 10), B) d-Sorbitol (SRB, 500 μM, day 10), C)(R/S)-Baclofen (BCL, 5 μM, day 10) and D) Naltrexone (NTX, 5 μM, day 10)on MBP expression. *:p<0.05: significantly different from control(=ascorbic acid) (One-Way ANOVA followed by Fisher Post-hoc test); ns:not statistically different

FIG. 2. Synergistic effect of drug combination, dose 6 A) Mix7 (dose 6,day 10), B) SRB (160 nM, day 10), C) BCL (1.6 nM, day 10) and D) NTX(1.6 nM, day 10) on MBP expression. *:p<0.05: significantly differentfrom control (=ascorbic acid) (One-Way ANOVA followed by Fisher Post-hoctest); ns: not statistically different

FIG. 3. Positive effect of Mix7 (7 doses) A) on day 10 and B) on day 11in co-incubation with ascorbic acid in PMP22 TG co-cultures on MBPexpression in percentage of control (=ascorbic acid). One-Way Anovafollowed by Fisher post-hoc test.

FIG. 4. Positive effect on male rats of the 3 and 6 weeks treatment withMix1 measured using bar test. Latencies were measured as the mean of twofirst assays of the tests (white bars represent control rats treatedwith placebo; black bars represent transgenic rats treated with placebo;grey bars represent transgenic rats treated with Mix1. ** p<0.01.Statistics are realised with the Student bilateral test).

FIG. 5. Positive effect on gait of male rats of the 3 and 6-week(respectively left and right graph treatment with Mix1 composition(white bars represent fluid gait; grey bars represent not fluid gait;black bars represent rats with a severe incapacity to walk. Statisticsare realised with the Student bilateral test).

FIG. 6. Positive effect on male rats of the Mix1 composition in ratsusing inclined plane test (25°). Rats were examined after 3, 6, 9 and 12weeks of treatment (white bars represent control rats treated withplacebo; black bars represent transgenic rats treated with placebo; greybars represent transgenic rats treated with Mix1. * p<0.05. Statisticsare realised with the Student bilateral test).

FIG. 7. Positive effect on female rats of the 3 weeks treatment with theMix2 composition in rats, using an inclined plane test (white barsrepresent control rats treated with placebo; black bars representtransgenic rats treated with placebo; grey bars represent transgenicrats treated with Mix2. ** p<0.01. Statistics are realised with theStudent bilateral test).

FIG. 8. Protective effect on male rats of Mix1 on oxaliplatin-inducedneuropathy (white bars represent wild type rats treated with placebo;black bars represent wild type rats treated with reference productgabapentin; grey bars represent wild type rats treated with Mix1. *p<0.05; ** p<0.01. Statistics are realised with the Student bilateraltest).

FIG. 9. Significant decrease of pmp22 RNA expression in treatedtransgenic animals compared to PMP22 transgenic rats, observed after 9weeks of treatment with the Mix7-dose 3 (MPZ as reference gene, Seredaet al, 1996) (p=0.0015). The transgene integration and theoverexpression of pmp22 gene have also been confirmed; pmp22 RNA intransgenic PMP22 rats was 1.8 fold overexpressed compared to their wildtype littermates controls (p<1·10−4). Extraction of pmp22 RNA wasperformed on sciatic nerves of 16 weeks old male rats (n=18 for the WildType, n=20 for the transgenic rats and n=18 for TG treated withMix7-dose3). Statistical analysis was performed by using the Welcht-test.

FIG. 10. A clustering analysis was performed on the inclined plane testscore at 35° (to distribute in the poor, intermediate and goodperformance classes at all time points of evaluation (3, 6 and 9 weeksof treatment analyzed together). A significant difference was observedbetween WT and TG placebo: 68% of WT belonged to the good performancesgroup and only 5% of TG placebo belonged to this group (p=0.0003).Mix7-dose 2 and dose 3 improved the performances of TG rats. Statisticalanalysis were performed by applying a trend-test at the 5% significancelevel (n=18 for WT placebo rats, n=20 for TG placebo rats, n=17 for TGtreated with Mix7-dose 2, n=18 for TG treated with Mix7-dose3).

FIG. 11. The fall latencies of TG rats in the bar test after 9 weeks oftreatment with Mix7-dose3 were analyzed using a Cox model with asandwich variance estimator, and compared to the reference TG placebo byapplying a log rank-test at the 5% significance level. Mix7-dose 3significantly increased the fall latency of TG rats after 9 weeks oftreatment.

FIG. 12. The grip strength of groups of wild type, transgenic placeboand transgenic animals treated with Mix7-dose 3 daily for 9 weeks wasmodelized using a Cox model with a sandwich variance estimator over allthe times after treatment (3, 6 and 9 weeks) and compared to thereference TG placebo by applying a log rank-test at the 5% significancelevel. The corresponding p-values were presented on Kaplan-Meier curvesA significant decrease of the fore paws grip strength of transgenicplacebo rats was observed (black plain line, n=21) compared to WT rats(grey plain line, p=1.45·10−5, n=19). The treatment with Mix7-dose 3significantly increased the strength of the fore paws (black dashedline; p=0.03, n=18).

FIG. 13. A Pearson correlation test showed a significant correlationbetween the fall latency time in the bar test (after 9 weeks oftreatment) and the pmp22 RNA expression level: p=1.6·10⁻⁴ (WT, TGplacebo and TG treated with the Mix7-dose 3 analysed together); p=0.07(TG placebo and TG treated with the Mix7-dose 3 analysed together).

The lower the pmp22 RNA expression was, the better the bar testperformances were. Male rats were 16 weeks old (n=18 for WT rats, whitecircles; n=20 for the TG placebo, black circles and n=18 for TG treatedwith the Mix7-dose3, white triangles).

FIG. 14. A Pearson correlation test showed a significant correlationbetween the fall latency time in the bar test (after 9 weeks oftreatment) and the conduction velocity of the sensitive nerve (NCV):p=1.34·10−6 (WT, TG placebo and TG treated with Mix7-dose3 analysedtogether) and p=0.04 (TG placebo and TG treated with Mix7-dose3 analysedtogether). The higher the conduction velocity was, the better theperformances in bar test were. Male rats were 16 weeks old (n=18 for WTrats, white circles; n=20 for the TG placebo, black circles and n=18 forTG treated with the Mix7-dose3, white triangles).

DETAILED DESCRIPTION OF THE INVENTION

The present invention provides new therapeutic approaches for treatingCMT or related disorders. The invention discloses novel drugcombinations which allow an effective correction of such diseases andmay be used in any mammalian subject.

Within the context of this invention, CMT includes CMT1A, CMT1B, CMT1C,CMT1D, CMT1X, CMT2A, CMT2B, CMT2D, CMT2E, CMT2-P0, CMT4A, CMT4B1,CMT4B2, CMT4D, CMT4F, CMT4, or AR-CMT2A, more preferably CMT1a.

Within the context of the present invention, the term “CMT relateddisorder” designates other diseases associated with abnormal expressionof PMP22 leading to abnormal myelination and loss of neurons. The term“CMT related disorder” more particularly includes Alzheimer's disease(AD), senile dementia of AD type (SDAT), Parkinson's disease, Lewis bodydementia, vascular dementia, autism, mild cognitive impairment (MCI),age-associated memory impairment (AAMI) and problem associated withageing, post-encephalitic Parkinsonism, schizophrenia, depression,bipolar disease and other mood disorders, Huntington's disease, motorneurone diseases including amyotrophic lateral sclerosis (ALS), multiplesclerosis, idiopathic neuropathies, diabetic neuropathy, toxicneuropathy including neuropathy induced by drug treatments, neuropathiesprovoked by HIV, radiation, heavy metals and vitamin deficiency states,prion-based neurodegeneration, including Creutzfeld-Jakob disease (CJD),bovine spongiform encephalopathy (BSE), GSS, FFI, Kuru and Alper'ssyndrome.

In a preferred embodiment, “CMT related disorder” designates a toxicneuropathy, particularly drug-induced neuropathies, or ALS.

As used herein, “treatment” of a disorder includes the therapy,prevention, prophylaxis, retardation or reduction of pain provoked bythe disorder. The term treatment includes in particular the control ofdisease progression and associated symptoms.

Also, the term “compound” designates the chemical compounds asspecifically named in the application, as well as any pharmaceuticallycomposition with acceptable salt, hydrate, ester, ether, isomers,racemate, conjugates, pro-drugs thereof. The compounds listed in thisapplication may also be identified with its corresponding CAS number.

Thus, the preferred compounds used in the invention are Baclofen (CAS1134-47-0) and its possible salts, enantiomers, racemates, prodrugs andderivatives; Sorbitol (CAS 50-70-4) and its possible salts, enantiomers,racemates, prodrugs and derivatives; Naltrexone (CAS 16590-41-3) and itspossible salts, enantiomers, racemates, prodrugs and derivatives;Mifepristone (CAS 84371-65-3) and its possible salts, enantiomers,racemates, prodrugs and derivatives; Pilocarpine (CAS 54-71-7) and itspossible salts, enantiomers, racemates, prodrugs and derivatives;Methimazole (CAS 60-56-0) and its possible salts, enantiomers,racemates, prodrugs and derivatives; Ketoprofen (CAS 22071-15-4) and itspossible salts, enantiomers, racemates, prodrugs and derivatives;Flurbiprofen (5104-49-4) and its possible salts, enantiomers, racemates,prodrugs and derivatives and Rapamycin (CAS 53123-88-9) and its possiblesalts, enantiomers, racemates, prodrugs and derivatives.

Further compounds used in the invention are Acetazolamide (CAS 59-66-5)and its possible salts, enantiomers, prodrugs and derivatives; Albuterol(CAS 18559-94-9) and its possible salts, enantiomers, prodrugs andderivatives; Amiloride (CAS 2016-88-8) and its possible salts,enantiomers, prodrugs and derivatives; Aminoglutethimide (CAS 125-84-8)and its possible salts, enantiomers, prodrugs and derivatives;Amiodarone (CAS 1951-25-3) and its possible salts, enantiomers, prodrugsand derivatives; Aztreonam (CAS 78110-38-0) and its possible salts,enantiomers, prodrugs and derivatives; Baclofen (CAS 1134-47-0) and itspossible salts, enantiomers, prodrugs and derivatives; Balsalazide (CAS80573-04-2) and its possible salts, enantiomers, prodrugs andderivatives; Betaine (CAS 107-43-7) and its possible salts, enantiomers,prodrugs and derivatives; Bethanechol (CAS 674-38-4) and its possiblesalts, enantiomers, prodrugs and derivatives; Bicalutamide (CAS90357-06-5) and its possible salts, enantiomers, prodrugs andderivatives; Bromocriptine (CAS 25614-03-3) and its possible salts,enantiomers, prodrugs and derivatives; Bumetanide (CAS 28395-03-1) andits possible salts, enantiomers, prodrugs and derivatives; Buspirone(CAS 36505-84-7) and its possible salts, enantiomers, prodrugs andderivatives; Carbachol (CAS 51-83-2) and its possible salts,enantiomers, prodrugs and derivatives; Carbamazepine (CAS 298-46-4) andits possible salts, enantiomers, prodrugs and derivatives; Carbimazole(CAS 22232-54-8) and its possible salts, enantiomers, prodrugs andderivatives; Cevimeline (CAS 107233-08-9) and its possible salts,enantiomers, prodrugs and derivatives; Ciprofloxacin (CAS 85721-33-1)and its possible salts, enantiomers, prodrugs and derivatives; Clonidine(CAS 4205-90-7) and its possible salts, enantiomers, prodrugs andderivatives; Curcumin (CAS 458-37-7) and its possible salts,enantiomers, prodrugs and derivatives; Cyclosporine A (CAS 59865-13-3)and its possible salts, enantiomers, prodrugs and derivatives; Diazepam(CAS 439-14-5) and its possible salts, enantiomers, prodrugs andderivatives; Diclofenac (CAS 15307-86-5) and its possible salts,enantiomers, prodrugs and derivatives; Dinoprostone (CAS 363-24-6) andits possible salts, enantiomers, prodrugs and derivatives; Disulfiram(CAS 97-77-8) and its possible salts, enantiomers, prodrugs andderivatives; D-Sorbitol (CAS 50-70-4) and its possible salts,enantiomers, prodrugs and derivatives; Dutasteride (CAS 164656-23-9) andits possible salts, enantiomers, prodrugs and derivatives; Estradiol(CAS 50-28-2) and its possible salts, enantiomers, prodrugs andderivatives; Exemestane (CAS 107868-30-4) and its possible salts,enantiomers, prodrugs and derivatives; Felbamate (CAS 25451-15-4) andits possible salts, enantiomers, prodrugs and derivatives; Fenofibrate(CAS 49562-28-9) and its possible salts, enantiomers, prodrugs andderivatives; Finasteride (CAS 98319-26-7) and its possible salts,enantiomers, prodrugs and derivatives; Flumazenil (CAS 78755-81-4) andits possible salts, enantiomers, prodrugs and derivatives; Flunitrazepam(CAS 1622-62-4) and its possible salts, enantiomers, prodrugs andderivatives; Flurbiprofen (CAS 5104-49-4) and its possible salts,enantiomers, prodrugs and derivatives; Furosemide (CAS 54-31-9) and itspossible salts, enantiomers, prodrugs and derivatives; Gabapentin (CAS60142-96-3) and its possible salts, enantiomers, prodrugs andderivatives; Galantamine (CAS 357-70-0) and its possible salts,enantiomers, prodrugs and derivatives; Haloperidol (CAS 52-86-8) and itspossible salts, enantiomers, prodrugs and derivatives; Ibuprofen (CAS15687-27-1) and its possible salts, enantiomers, prodrugs andderivatives; Isoproterenol (CAS 7683-59-2) and its possible salts,enantiomers, prodrugs and derivatives; Ketoconazole (CAS 65277-42-1) andits possible salts, enantiomers, prodrugs and derivatives; Ketoprofen(CAS 22071-15-4) and its possible salts, enantiomers, prodrugs andderivatives; L-carnitine (CAS 541-15-1) and its possible salts,enantiomers, prodrugs and derivatives; Liothyronine (T3) (CAS 6893-02-3)and its possible salts, enantiomers, prodrugs and derivatives; Lithium(CAS 7439-93-2) and its possible salts, enantiomers, prodrugs andderivatives; Losartan (CAS 114798-26-4) and its possible salts,enantiomers, prodrugs and derivatives; Loxapine (CAS 1977-10-2) and itspossible salts, enantiomers, prodrugs and derivatives; Meloxicam (CAS71125-38-7) and its possible salts, enantiomers, prodrugs andderivatives; Metaproterenol (CAS 586-06-1) and its possible salts,enantiomers, prodrugs and derivatives; Metaraminol (CAS 54-49-9) and itspossible salts, enantiomers, prodrugs and derivatives; Metformin (CAS657-24-9) and its possible salts, enantiomers, prodrugs and derivatives;Methacholine (CAS 55-92-5) and its possible salts, enantiomers, prodrugsand derivatives; Methimazole (CAS 60-56-0) and its possible salts,enantiomers, prodrugs and derivatives; Methylergonovine (CAS 113-42-8)and its possible salts, enantiomers, prodrugs and derivatives;Metoprolol (CAS 37350-58-6) and its possible salts, enantiomers,prodrugs and derivatives; Metyrapone (CAS 54-36-4) and its possiblesalts, enantiomers, prodrugs and derivatives; Miconazole (CAS22916-47-8) and its possible salts, enantiomers, prodrugs andderivatives; Mifepristone (CAS 84371-65-3) and its possible salts,enantiomers, prodrugs and derivatives; Nadolol (CAS 42200-33-9) and itspossible salts, enantiomers, prodrugs and derivatives; Naloxone (CAS465-65-6) and its possible salts, enantiomers, prodrugs and derivatives;Naltrexone (CAS 16590-41-3) and its possible salts, enantiomers,prodrugs and derivatives; Norfloxacin (CAS 70458-96-7) and its possiblesalts, enantiomers, prodrugs and derivatives; Pentazocine (CAS 359-83-1)and its possible salts, enantiomers, prodrugs and derivatives;Phenoxybenzamine (CAS 59-96-1) and its possible salts, enantiomers,prodrugs and derivatives; Phenylbutyrate (CAS 1821-12-1) and itspossible salts, enantiomers, prodrugs and derivatives; Pilocarpine (CAS54-71-7) and its possible salts, enantiomers, prodrugs and derivatives;Pioglitazone (CAS 111025-46-8) and its possible salts, enantiomers,prodrugs and derivatives; Prazosin (CAS 19216-56-9) and its possiblesalts, enantiomers, prodrugs and derivatives; Propylthiouracil (CAS51-52-5) and its possible salts, enantiomers, prodrugs and derivatives;Raloxifene (CAS 84449-90-1) and its possible salts, enantiomers,prodrugs and derivatives; Rapamycin (CAS 53123-88-9) and its possiblesalts, enantiomers, prodrugs and derivatives; Rifampin (CAS 13292-46-1)and its possible salts, enantiomers, prodrugs and derivatives;Simvastatin (CAS 79902-63-9) and its possible salts, enantiomers,prodrugs and derivatives; Spironolactone (CAS 52-01-7) and its possiblesalts, enantiomers, prodrugs and derivatives; Tacrolimus (CAS104987-11-3) and its possible salts, enantiomers, prodrugs andderivatives; Tamoxifen (CAS 10540-29-1) and its possible salts,enantiomers, prodrugs and derivatives; Trehalose (CAS 99-20-7) and itspossible salts, enantiomers, prodrugs and derivatives; Trilostane (CAS13647-35-3) and its possible salts, enantiomers, prodrugs andderivatives; Valproic acid (CAS 99-66-1) and its possible salts,enantiomers, prodrugs and derivatives.

The term “combination” designates a treatment wherein several drugs areco-administered to a subject to cause a biological effect. In a combinedtherapy, the drugs may be administered together or separately, at thesame time or sequentially. Also, the drugs may be administered throughdifferent routes and protocols.

The invention now discloses the identification and activities ofparticular drug combinations which provide an efficient treatment forCMT. More specifically, the invention discloses novel ternarycombinations which provide a significant effect in vitro and in vivo onCMT or related disorders.

In this regard, the invention relates to a composition comprisingBaclofen, Sorbitol and a compound selected from Pilocarpine,Methimazole, Mifepristone, Naltrexone, Rapamycine, Flurbiprofen andKetoprofen, salts, enantiomers, racemates, or prodrugs thereof.

More preferably, the invention relates to a composition comprisingBaclofen, Sorbitol and a compound selected from Pilocarpine,Methimazole, Mifepristone, Naltrexone, and Ketoprofen.

In the most preferred embodiment, the present invention relates to acomposition comprising Naltrexone, Baclofen and Sorbitol, forsimultaneous, separate or sequential administration to a mammaliansubject.

Preferably, in the above compositions, Sorbitol is D-Sorbitol andBaclofen is RS-Baclofen or S-Baclofen, more preferably RS-baclofen.

Another preferred object of the invention relates to a compositioncomprising:

-   -   (a) rapamycin,    -   (b) mifepristone or naltrexone, and    -   (c) a PMP22 modulator,        for simultaneous, separate or sequential administration to a        mammalian subject.

Another preferred object of this invention is a composition comprising:

-   -   (a) rapamycin,    -   (b) mifepristone, and    -   (c) a PMP22 modulator,        for simultaneous, separate or sequential administration to a        mammalian subject.

The PMP22 modulator may be any compound that modulates PMP22 pathway ina cell and essentially causes or contributes to normalization of myelinorganization and/or inhibition of neuron loss. The PMP22 modulator maybe selected from Acetazolamide, Albuterol, Amiloride, Aminoglutethimide,Amiodarone, Aztreonam, Baclofen, Balsalazide, Betaine, Bethanechol,Bicalutamide, Bromocriptine, Bumetanide, Buspirone, Carbachol,Carbamazepine, Carbimazole, Cevimeline, Ciprofloxacin, Clonidine,Curcumin, Cyclosporine A, Diazepam, Diclofenac, Dinoprostone,Disulfiram, D-Sorbitol, Dutasteride, Estradiol, Exemestane, Felbamate,Fenofibrate, Finasteride, Flumazenil, Flunitrazepam, Flurbiprofen,Furosemide, Gabapentin, Galantamine, Haloperidol, Ibuprofen,Isoproterenol, Ketoconazole, Ketoprofen, L-carnitine, Liothyronine (T3),Lithium, Losartan, Loxapine, Meloxicam, Metaproterenol, Metaraminol,Metformin, Methacholine, Methimazole, Methylergonovine, Metoprolol,Metyrapone, Miconazole, Mifepristone, Nadolol, Naloxone, Naltrexone;Norfloxacin, Pentazocine, Phenoxybenzamine, Phenylbutyrate, Pilocarpine,Pioglitazone, Prazosin, Propylthiouracil, Raloxifene, Rapamycin,Rifampin, Simvastatin, Spironolactone, Tacrolimus, Tamoxifen, Trehalose,Trilostane, Valproic acid salts or prodrugs thereof.

In a preferred embodiment, compound (c) is selected from pilocarpin,methimazole and baclofen. In this regard, a most preferred compositionof this invention comprises:

-   -   (a) rapamycin,    -   (b) mifepristone, and    -   (c) a compound selected from pilocarpin, methimazole and        baclofen,        for simultaneous, separate or sequential administration to a        mammalian subject.

Specific examples of such compositions include compositions comprising:

-   -   Rapamycin; mifepristone and pilocarpin;    -   Rapamycin; mifepristone and Baclofen;    -   Rapamycin; mifepristone and methimazole; or    -   Rapamycin; Naltrexone and methimazole.

The experimental section shows these particular drug combinations areable to efficiently correct PMP22 expression in vitro, to restore normalmyelination and neuron integrity, and thus to ameliorate CMT in animalsin vivo. The results also show these combinations can protect animalsfrom chemotherapy-induced neuropathy. As a result, these compositionsmay be used to prevent or reduce chemotherapy-induced neuropathy,thereby allowing patients to receive chemotherapy for longer periods.

Another object of this invention is a composition comprising Naltrexone,Baclofen and a further distinct PMP22 inhibitor as defined above.

A further object of this invention is a composition as disclosed abovefurther comprising one or several pharmaceutically acceptable excipientsor carriers (i.e., a pharmaceutical composition).

Another object of the present invention relates to a composition asdisclosed above for treating CMT or a related disorder.

A further object of this invention relates to the use of a combinationof compounds as disclosed above for the manufacture of a medicament forthe treatment of CMT or a related disorder.

A further object of this invention is a method for treating CMT or arelated disorder, the method comprising administering to a subject inneed thereof an effective amount of a composition as defined above.

A further object of this invention is a method of preparing apharmaceutical composition, the method comprising mixing the abovecompounds in an appropriate excipient or carrier.

A more specific object of this invention is a method of treating CMT1ain a subject, the method comprising administering to the subject in needthereof an effective amount of a compound or combination of compounds asdisclosed above.

A further specific object of this invention is a method of treatingtoxic neuropathy in a subject, the method comprising administering tothe subject in need thereof an effective amount of a compound orcombination of compounds as disclosed above.

A further specific object of this invention is a method of treating ALSin a subject, the method comprising administering to the subject in needthereof an effective amount of a compound or combination of compounds asdisclosed above.

Therapy according to the invention may be performed as drug combinationand/or in conjunction with any other therapy. It and may be provided athome, the doctor's office, a clinic, a hospital's outpatient department,or a hospital, so that the doctor can observe the therapy's effectsclosely and make any adjustments that are needed.

The duration of the therapy depends on the stage of the disease beingtreated, the age and condition of the patient, and how the patientresponds to the treatment.

Additionally, a person having a greater risk of developing an additionalneuropathic disorder (e.g., a person who is genetically predisposed toor have, for example, diabetes, or is being under treatment for anoncological condition, etc.) may receive prophylactic treatment toalleviate or to delay eventual neuropathic response.

The dosage, frequency and mode of administration of each component ofthe combination can be controlled independently. For example, one drugmay be administered orally while the second drug may be administeredintramuscularly. Combination therapy may be given in on-and-off cyclesthat include rest periods so that the patient's body has a chance torecovery from any as yet unforeseen side-effects. The drugs may also beformulated together such that one administration delivers both drugs.

Formulation of Pharmaceutical Compositions

The administration of each drug of the combination may be by anysuitable means that results in a concentration of the drug that,combined with the other component, is able to ameliorate the patientcondition (which may be determined e.g., in vitro by an effect onelevated expression of PMP22 upon reaching the peripheral nerves).

While it is possible for the active ingredients of the combination to beadministered as the pure chemical it is preferable to present them as apharmaceutical composition, also referred to in this context aspharmaceutical formulation. Possible compositions include those suitablefor oral, rectal, topical (including transdermal, buccal andsublingual), or parenteral (including subcutaneous, intramuscular,intravenous and intradermal) administration.

More commonly these pharmaceutical formulations are prescribed to thepatient in “patient packs” containing a number dosing units or othermeans for administration of metered unit doses for use during a distincttreatment period in a single package, usually a blister pack. Patientpacks have an advantage over traditional prescriptions, where apharmacist divides a patient's supply of a pharmaceutical from a bulksupply, in that the patient always has access to the package insertcontained in the patient pack, normally missing in traditionalprescriptions. The inclusion of a package insert has been shown toimprove patient compliance with the physician's instructions. Thus, theinvention further includes a pharmaceutical formulation, as hereinbefore described, in combination with packaging material suitable forsaid formulations. In such a patient pack the intended use of aformulation for the combination treatment can be inferred byinstructions, facilities, provisions, adaptations and/or other means tohelp using the formulation most suitably for the treatment. Suchmeasures make a patient pack specifically suitable for and adapted foruse for treatment with the combination of the present invention.

The drug may be contained in any appropriate amount in any suitablecarrier substance, and is may be present in an amount of 1-99% by weightof the total weight of the composition. The composition may be providedin a dosage form that is suitable for the oral, parenteral (e.g.,intravenously, intramuscularly), rectal, cutaneous, nasal, vaginal,inhalant, skin (patch), or ocular administration route. Thus, thecomposition may be in the form of, e.g., tablets, capsules, pills,powders, granulates, suspensions, emulsions, solutions, gels includinghydrogels, pastes, ointments, creams, plasters, drenches, osmoticdelivery devices, suppositories, enemas, injectables, implants, sprays,or aerosols.

The pharmaceutical compositions may be formulated according toconventional pharmaceutical practice (see, e.g., Remington: The Scienceand Practice of Pharmacy (20th ed.), ed. A. R. Gennaro, LippincottWilliams & Wilkins, 2000 and Encyclopedia of Pharmaceutical Technology,eds. J. Swarbrick and J. C. Boylan, 1988-1999, Marcel Dekker, New York).

Pharmaceutical compositions according to the invention may be formulatedto release the active drug substantially immediately upon administrationor at any predetermined time or time period after administration.

The controlled release formulations include (i) formulations that createa substantially constant concentration of the drug within the body overan extended period of time; (ii) formulations that after a predeterminedlag time create a substantially constant concentration of the drugwithin the body over an extended period of time; (iii) formulations thatsustain drug action during a predetermined time period by maintaining arelatively, constant, effective drug level in the body with concomitantminimization of undesirable side effects associated with fluctuations inthe plasma level of the active drug substance; (iv) formulations thatlocalize drug action by, e.g., spatial placement of a controlled releasecomposition adjacent to or in the diseased tissue or organ; and (v)formulations that target drug action by using carriers or chemicalderivatives to deliver the drug to a particular target cell type.

Administration of drugs in the form of a controlled release formulationis especially preferred in cases in which the drug in combination, has(i) a narrow therapeutic index (i.e., the difference between the plasmaconcentration leading to harmful side effects or toxic reactions and theplasma concentration leading to a therapeutic effect is small; ingeneral, the therapeutic index, TI, is defined as the ratio of medianlethal dose (LD50) to median effective dose (ED50)); (ii) a narrowabsorption window in the gastro-intestinal tract; or (iii) a very shortbiological half-life so that frequent dosing during a day is required inorder to sustain the plasma level at a therapeutic level.

Any of a number of strategies can be pursued in order to obtaincontrolled release in which the rate of release outweighs the rate ofmetabolism of the drug in question. Controlled release may be obtainedby appropriate selection of various formulation parameters andingredients, including, e.g., various types of controlled releasecompositions and coatings. Thus, the drug is formulated with appropriateexcipients into a pharmaceutical composition that, upon administration,releases the drug in a controlled manner (single or multiple unit tabletor capsule compositions, oil solutions, suspensions, emulsions,microcapsules, microspheres, nanoparticles, patches, and liposomes).

Solid Dosage Forms for Oral Use

Formulations for oral use include tablets containing the activeingredient(s) in a mixture with non-toxic pharmaceutically acceptableexcipients. These excipients may be, for example, inert diluents orfillers (e.g., sucrose, microcrystalline cellulose, starches includingpotato starch, calcium carbonate, sodium chloride, calcium phosphate,calcium sulfate, or sodium phosphate); granulating and disintegratingagents (e.g., cellulose derivatives including microcrystallinecellulose, starches including potato starch, croscarmellose sodium,alginates, or alginic acid); binding agents (e.g., acacia, alginic acid,sodium alginate, gelatin, starch, pregelatinized starch,microcrystalline cellulose, carboxymethylcellulose sodium,methylcellulose, hydroxypropyl methylcellulose, ethylcellulose,polyvinylpyrrolidone, or polyethylene glycol); and lubricating agents,glidants, and antiadhesives (e.g., stearic acid, silicas, or talc).Other pharmaceutically acceptable excipients can be colorants, flavoringagents, plasticizers, humectants, buffering agents, and the like.

The tablets may be uncoated or they may be coated by known techniques,optionally to delay disintegration and absorption in thegastrointestinal tract and thereby providing a sustained action over alonger period. The coating may be adapted to release the active drugsubstance in a predetermined pattern (e.g., in order to achieve acontrolled release formulation) or it may be adapted not to release theactive drug substance until after passage of the stomach (entericcoating). The coating may be a sugar coating, a film coating (e.g.,based on hydroxypropyl methylcellulose, methylcellulose, methylhydroxyethylcellulose, hydroxypropylcellulose, carboxymethylcellulose,acryl ate copolymers, polyethylene glycols and/or polyvinylpyrrolidone),or an enteric coating (e.g., based on methacrylic acid copolymer,cellulose acetate phthalate, hydroxypropyl methylcellulose phthalate,hydroxypropyl methylcellulose acetate succinate, polyvinyl acetatephthalate, shellac, and/or ethylcellulose). A time delay material suchas, e.g., glyceryl monostearate or glyceryl distearate may be employed.

The solid tablet compositions may include a coating adapted to protectthe composition from unwanted chemical changes, (e.g., chemicaldegradation prior to the release of the active drug substance). Thecoating may be applied on the solid dosage form in a similar manner asthat described in Encyclopedia of Pharmaceutical Technology.

The drugs may be mixed together in the tablet, or may be partitioned.For example, a first drug is contained on the inside of the tablet, anda second drug is on the outside, such that a substantial portion of thesecond drug is released prior to the release of the first drug.

Formulations for oral use may also be presented as chewable tablets, oras hard gelatin capsules wherein the active ingredient is mixed with aninert solid diluent (e.g., potato starch, microcrystalline cellulose,calcium carbonate, calcium phosphate or kaolin), or as soft gelatincapsules wherein the active ingredient is mixed with water or an oilmedium, for example, liquid paraffin, or olive oil. Powders andgranulates may be prepared using the ingredients mentioned above undertablets and capsules in a conventional manner.

Controlled release compositions for oral use may, e.g., be constructedto release the active drug by controlling the dissolution and/or thediffusion of the active drug substance.

Dissolution or diffusion controlled release can be achieved byappropriate coating of a tablet, capsule, pellet, or granulateformulation of drugs, or by incorporating the drug into an appropriatematrix. A controlled release coating may include one or more of thecoating substances mentioned above and/or, e.g., shellac, beeswax,glycowax, castor wax, carnauba wax, stearyl alcohol, glycerylmonostearate, glyceryl distearate, glycerol palmitostearate,ethylcellulose, acrylic resins, dl-polylactic acid, cellulose acetatebutyrate, polyvinyl chloride, polyvinyl acetate, vinyl pyrrolidone,polyethylene, polymethacrylate, methylmethacrylate,2-hydroxymethacrylate, methacrylate hydrogels, 1,3 butylene glycol,ethylene glycol methacrylate, and/or polyethylene glycols. In acontrolled release matrix formulation, the matrix material may alsoinclude, e.g., hydrated metylcellulose, carnauba wax and stearylalcohol, carbopol 934, silicone, glyceryl tristearate, methylacrylate-methyl methacrylate, polyvinyl chloride, polyethylene, and/orhalogenated fluorocarbon.

A controlled release composition containing one or more of the drugs ofthe claimed combinations may also be in the form of a buoyant tablet orcapsule (i.e., a tablet or capsule that, upon oral administration,floats on top of the gastric content for a certain period of time). Abuoyant tablet formulation of the drug(s) can be prepared by granulatinga mixture of the drug(s) with excipients and 20-75% w/w ofhydrocolloids, such as hydroxyethylcellulose, hydroxypropylcellulose, orhydroxypropylmethylcellulose. The obtained granules can then becompressed into tablets. On contact with the gastric juice, the tabletforms a substantially water-impermeable gel barrier around its surface.This gel barrier takes part in maintaining a density of less than one,thereby allowing the tablet to remain buoyant in the gastric juice.

Liquids for Oral Administration

Powders, dispersible powders, or granules suitable for preparation of anaqueous suspension by addition of water are convenient dosage forms fororal administration. Formulation as a suspension provides the activeingredient in a mixture with a dispersing or wetting agent, suspendingagent, and one or more preservatives. Suitable suspending agents are,for example, sodium carboxymethylcellulose, methylcellulose, sodiumalginate, and the like.

Parenteral Compositions

The pharmaceutical composition may also be administered parenterally byinjection, infusion or implantation (intravenous, intramuscular,subcutaneous, or the like) in dosage forms, formulations, or viasuitable delivery devices or implants containing conventional, non-toxicpharmaceutically acceptable carriers and adjuvants. The formulation andpreparation of such compositions are well known to those skilled in theart of pharmaceutical formulation.

Compositions for parenteral use may be provided in unit dosage forms(e.g., in single-dose ampoules), or in vials containing several dosesand in which a suitable preservative may be added (see below). Thecomposition may be in form of a solution, a suspension, an emulsion, aninfusion device, or a delivery device for implantation or it may bepresented as a dry powder to be reconstituted with water or anothersuitable vehicle before use. Apart from the active drug(s), thecomposition may include suitable parenterally acceptable carriers and/orexcipients. The active drug(s) may be incorporated into microspheres,microcapsules, nanoparticles, liposomes, or the like for controlledrelease. The composition may include suspending, solubilizing,stabilizing, pH-adjusting agents, and/or dispersing agents.

The pharmaceutical compositions according to the invention may be in theform suitable for sterile injection. To prepare such a composition, thesuitable active drug(s) are dissolved or suspended in a parenterallyacceptable liquid vehicle. Among acceptable vehicles and solvents thatmay be employed are water, water adjusted to a suitable pH by additionof an appropriate amount of hydrochloric acid, sodium hydroxide or asuitable buffer, 1,3-butanediol, Ringer's solution, and isotonic sodiumchloride solution. The aqueous formulation may also contain one or morepreservatives (e.g., methyl, ethyl or n-propyl p-hydroxybenzoate). Incases where one of the drugs is only sparingly or slightly soluble inwater, a dissolution enhancing or solubilizing agent can be added, orthe solvent may include 10-60% w/w of propylene glycol or the like.

Controlled release parenteral compositions may be in form of aqueoussuspensions, microspheres, microcapsules, magnetic microspheres, oilsolutions, oil suspensions, or emulsions. Alternatively, the activedrug(s) may be incorporated in biocompatible carriers, liposomes,nanoparticles, implants, or infusion devices. Materials for use in thepreparation of microspheres and/or microcapsules are, e.g.,biodegradable/bioerodible polymers such as polygalactin, poly-(isobutylcyanoacrylate), poly(2-hydroxyethyl-L-glutamnine). Biocompatiblecarriers that may be used when formulating a controlled releaseparenteral formulation are carbohydrates (e.g., dextrans), proteins(e.g., albumin), lipoproteins, or antibodies. Materials for use inimplants can be non-biodegradable (e.g., polydimethyl siloxane) orbiodegradable (e.g., poly(caprolactone), poly(glycolic acid) orpoly(ortho esters)).

Rectal Compositions

For rectal application, suitable dosage forms for a composition includesuppositories (emulsion or suspension type), and rectal gelatin capsules(solutions or suspensions). In a typical suppository formulation, theactive drug(s) are combined with an appropriate pharmaceuticallyacceptable suppository base such as cocoa butter, esterified fattyacids, glycerinated gelatin, and various water-soluble or dispersiblebases like polyethylene glycols. Various additives, enhancers, orsurfactants may be incorporated.

Percutaneous and Topical Compositions

The pharmaceutical compositions may also be administered topically onthe skin for percutaneous absorption in dosage forms or formulationscontaining conventionally non-toxic pharmaceutical acceptable carriersand excipients including micro spheres and liposomes. The formulationsinclude creams, ointments, lotions, liniments, gels, hydrogels,solutions, suspensions, sticks, sprays, pastes, plasters, and otherkinds of transdermal drug delivery systems. The pharmaceuticallyacceptable carriers or excipients may include emulsifying agents,antioxidants, buffering agents, preservatives, humectants, penetrationenhancers, chelating agents, gel-forming agents, ointment bases,perfumes, and skin protective agents.

The emulsifying agents may be naturally occurring gums (e.g., gum acaciaor gum tragacanth)

The preservatives, humectants, penetration enhancers may be parabens,such as methyl or propyl p-hydroxybenzoate, and benzalkonium chloride,glycerin, propylene glycol, urea, etc.

The pharmaceutical compositions described above for topicaladministration on the skin may also be used in connection with topicaladministration onto or close to the part of the body that is to betreated. The compositions may be adapted for direct application or forapplication by means of special drug delivery devices such as dressingsor alternatively plasters, pads, sponges, strips, or other forms ofsuitable flexible material.

Dosages and Duration of the Treatment

It will be appreciated that the drugs of the combination may beadministered concomitantly, either in the same or differentpharmaceutical formulation or sequentially. If there is sequentialadministration, the delay in administering one of the active ingredientsshould not be such as to lose the benefit of the efficacious effect ofthe combination of the active ingredients. A minimum requirement for acombination according to this description is that the combination shouldbe intended for combined use with the benefit of the efficacious effectof the combination of the active ingredients. The intended use of acombination can be inferred by facilities, provisions, adaptationsand/or other means to help using the combination according to theinvention.

Therapeutically effective amounts of the drugs that are subject of thisinvention can be used together for the preparation of a medicamentuseful for reducing the effect of increased expression of PMP22 gene;restoration of normal myelination and nerve integrity, preventing orreducing the risk of developing CMT disease, halting or slowing theprogression of CMT disease once it has become clinically manifest, andpreventing or reducing the risk of a first or subsequent occurrence ofan neuropathic event.

Although the active drugs of the present invention may be administeredin divided doses, for example two or three times daily, a single dailydose of each drug in the combination is preferred, with a single dailydose of all drugs in a single pharmaceutical composition (unit dosageform) being most preferred.

Administration can be one to several times daily for several days toseveral years, and may even be for the life of the patient. Chronic orat least periodically repeated long-term administration will beindicated in most cases.

-   -   The term “unit dosage form” refers to physically discrete units        (such as capsules, tablets, or loaded syringe cylinders)        suitable as unitary dosages for human subjects, each unit        containing a predetermined quantity of active material or        materials calculated to produce the desired therapeutic effect,        in association with the required pharmaceutical carrier.

The amount of each drug in the combination preferred for a unit dosagewill depend upon several factors including the administration method,the body weight and the age of the patient, the severity of theneuropathic damage caused by CMT disease or risk of potential sideeffects considering the general health status of the person to betreated.

Additionally, pharmacogenomic (the effect of genotype on thepharmacokinetic, pharmacodynamic or efficacy profile of a therapeutic)information about a particular patient may affect the dosage used.

Except when responding to especially impairing CMT disease cases whenhigher dosages may be required, or when treating children when lowerdosages should be chosen, the preferred dosage of each drug in thecombination will usually lie within the range of doses not above theusually prescribed for long-term maintenance treatment or proven to besafe in the large phase 3 clinical studies.

For example,

-   -   for Rapamycin, from about 1 to about 100 μg/kg per day,        typically from 1 to 50 μg/kg, for instance between 5 and 30        μg/kg/day.    -   for Mifepristone, from about 1 to about 300 μg/kg per day,        typically from 10 to 200 μg/kg, for instance between 10 and 80        μg/kg/day.    -   for Naltrexone, from about 1 to about 100 μg/kg per day,        typically from 1 to 50 μg/Kg, for instance between 1 and 20        μg/kg/day.    -   for Pilocarpin, from about 1 to about 100 μg/kg per day,        typically from 1 to 50 μg/Kg, for instance between 1 and 20 μ        g/kg/day.    -   for Baclofen, from about 1 to about 300 μg/kg per day, typically        from 10 to 200 μg/kg, for instance between 20 and 100 μg/kg/day.    -   for Methimazole, from about 1 to about 100 μg/kg per day,        typically from 1 to 50 μg/kg, for instance between 1 and 20        μg/kg/day.

The most preferred dosage will correspond to amounts from 1% up to 10%of those usually prescribed for long-term maintenance treatment.

It will be understood that the amount of the drug actually administeredwill be determined by a physician, in the light of the relevantcircumstances including the condition or conditions to be treated, theexact composition to be administered, the age, weight, and response ofthe individual patient, the severity of the patient's symptoms, and thechosen route of administration. Therefore, the above dosage ranges areintended to provide general guidance and support for the teachingsherein, but are not intended to limit the scope of the invention.

The following examples are given for purposes of illustration and not byway of limitation.

EXAMPLES A. Preparation of Drug Combinations

The following drug combinations were prepared:

Molecule dose Mix1 Sorbitol 2.1 mg/kg/day S-Baclofen (−) 60 μg/kg/dayNaltrexone 7 μg/kg/day Mix2 Rapamycin 15 μg/kg/day Mifepristone 40μg/kg/day Mix3 Rapamycin 15 μg/kg/day Mifepristone 40 μg/kg/dayPilocarpin 7 μg/kg/day Mix4 Rapamycin 15 μg/kg/day Mifepristone 40μg/kg/day Baclofen 60 μg/kg/day Mix5 Rapamycin 15 μg/kg/day Mifepristone40 μg/kg/day Methimazole 4.2 μg/kg/day Mix6 Rapamycin 15 μg/kg/dayNaltrexone 7 μg/kg/day Methimazole 4.2 μg/kg/day Molecule dose 1 dose 2dose 3 Mix7 Sorbitol 10.5 mg/kg/day 2.1 mg/kg/day 1.05 mg/kg/day (RS)0.3 mg/kg/day 60 μg/kg/day 30 μg/kg/day Baclofen Nal- 35 μg/kg/day 7μg/kg/day 3.5 μg/kg/day trexone

B. In Vitro Experiments 1. PMP22 Expression Assays on Schwann CellsTreated with Mix1-6 1.1 Cell Culture 1.1.1: Commercially Available RatPrimary Schwann Cells

Vials of rat Schwann cells (SC) primary culture (Sciencell # R1700) aredefrost and seeded at the density of 10 000 cells/cm2 in “SciencellSchwann cell medium” (basal medium from Sciencell # R1701) inpoly-L-lysine pre-coated 75 cm² flasks. The culture medium is composedof basal medium, 5% Fetal Bovine Serum (3H-Biomedical AB #1701-0025), 1%Schwann cell growth supplement (3H Biomedical AB #1701-1752), 1%Gentamicin (Sigma #G1397) and 10 μM of Forskolin (Sigma # F6886) topromote their proliferation.

After reaching confluency (4 to 10 days depending on cell batch),Schwann cells are purified by gentle agitation or by thy1.1immunopanning that allow SC isolation from adherent fibroblasts, toproduce cultures that are at least 95% pure. SC are then counted(Tryptan blue method) and seeded in poly-L-lysine pre-coated 75 cm²flask in the same SC medium. At confluency, cells are rinsed,trypsinized (trypsin-EDTA 1× diluted from Invitrogen #1540054), dilutedin PBS without calcium and magnesium) counted and platted in 12well-dishes (140 000 cells/well) in Sciencell Schwann cell medium with5% of FBS, 1% of cell growth supplement (CGS), 40 μg/ml of gentamicinand 4 μM Forskolin.

1.1.2 Custom-Made Rat Primary Schwann Cells

Primary Schwann cell cultures (SC) are established from Sprague-Dawleynewborn rats (between P0 and P2) sciatic nerves. All newborn rats aresacrificed and isolated in a Petri dish. Dissection is performed understerile conditions.

The dorsal skin is removed from the hind paw and the lower torso. Thesciatic nerve is isolated and transferred to a culture dish containingice-cold Leibovitz (L15, Invitrogen #11415) supplemented with 1%penicillin/streptomycin solution (50 UI/ml and 50 μg/ml, respectively;Invitrogen #15070) and 1% of bovine serum albumin (BSA, Sigma A6003).Both nerves per rats are transferred in a 15 ml tube containing ice-coldL15. The L15 medium is then removed and replaced by 2.4 ml of DMEM(Invitrogen #21969035) with 10 mg/ml of collagenase (Sigma #A6003).Nerves are incubated in this medium for 30 minutes at 37° C. The mediumis then removed and both nerves are dissociated by trypsin (10% trypsinEDTA 10×, Invitrogen #15400054) diluted in PBS without calcium andmagnesium (Invitrogen # 2007-03) for 20 min at 37° C. The reaction isstopped by addition of DMEM containing DNase I grade II (0.1 mg/ml Rochediagnostic #104159) and foetal calf serum (FCS 10%, Invitrogen #10270).The cell suspension was triturated with a 10 ml pipette and passedthrough a filter in a 50 ml tube (Swinnex 13 mm filter units, Millipore,with 20 μm nylon-mesh filters, Fisher). The cell suspension iscentrifuged at 350 g for 10 min at room temperature (RT) and the pelletsare suspended in DMEM with 10% FCS and 1% penicillin/streptomycin. Cellsare counted (Tryptan blue method) and seeded in Falcon 100 mm Primariatissue culture plates at the density of 5·10⁵ to 10⁶ cells/dish.

After one day of culture, the medium is changed with DMEM, 10% FCS, 1%penicillin/streptomycin and 10 μM of cytosine b-D-arabinofuranoside(Sigma #C1768). 48 hrs later, medium is eliminated and cells are washedthree times with DMEM. The SC growth medium is then added, composed ofDMEM, 10% FCS, 1% penicillin/streptomycin, 2 μM of Forskolin (Sigma#F6886), 10 μg/ml of bovine pituitary extract (PEX, Invitrogen #13028).The medium is replaced every 2-3 days.

After 8 days of culture (4 to 10 days depending on cell batches),Schwann cells reach confluency and the culture, containing a largeamount of contaminating fibroblasts, is purified by the thy1.1immunopanning method. After this purification, cells are suspended ingrowth medium at 10 000 cells/cm2 in poly-L-lysine pre-coated 75 cm²flasks. Once they reach confluency, cells are rinsed, trypsinized(trypsin-EDTA), counted and platted in 12 well-dishes (100 000cells/well).

1.1.3 Drug Incubation

After cells being platted in 12 well-dishes, the medium is replaced by adefined medium consisting in a mix of DMEM-F12 (Invitrogen # 21331020)complemented by 1% of N2 supplement (Invitrogen # 17502), 1% L-Glutamine(Invitrogen #25030024) 2.5% FBS (Sciencell #0025), 0.02 μg/ml ofcorticosterone (Sigma # C2505), 4 μM Forskolin and 50 μg/ml ofgentamycin. Growth factors are not added to this medium, to promote SCdifferentiation

24 hours later, the medium is replaced by a defined medium (DMEM-F12)complemented with 1% Insulin-Transferrin-Selenium-X (ITS, Invitrogen #51300), 16 μg/ml of Putrescine (Sigma # P5780), 0.02 μg/ml ofcorticosterone and 50 μg/ml of gentamicin. At this step, neitherprogesterone nor forskolin are present in the medium.

One day later, Schwann cells are stimulated by combinations of drugsduring 24 hrs (3 wells/condition). The preparation of each compound isperformed just prior to its addition to the cell culture medium.

Drugs are added to a defined medium composed of DMEM-F12, with 1%Insulin-Transferrin-Selenium-X (ITS, Invitrogen # 51300), 16 μg/ml ofPutrescine, 0.02 μg/ml of corticosterone, 10 nM Progesterone and 50μg/ml of gentamicin. The absence of Forskolin during drug stimulationavoids adenylate cyclase saturation.

1.2. Schwann Cells Purification by Thy1.1 Immunopanning

To prevent fibroblast culture contamination, Schwann cells are purifiedusing the clone Thy1.1 (ATCC TIB-103™) immunopanning protocole.

Antibody pre-coated 100 mm bacteria Petri dishes are prepared asfollows: these dishes are washed three times with PBS and treated by 20ml of Tris HCl solution 50 mM, pH 9.5, with 10 μg/ml of goat Anti-MouseIgM MU antibody (Jackson ImmunoResearch #115-005-020) overnight at 4°C.; then rinsed 3 times with PBS and treated by a solution of PBS with0.02% of BSA and supernatant obtained from T11D7e2 hybridoma culture(ATCC #TIB-103) containing the Thy1.1 IgM antibody for 2 hours at roomtemperature. Finally, the plates are washed three times with PBS beforethe cell suspensions are added.

SC are detached with trypsin EDTA. As soon as the majority of cells arein suspension, the trypsin is neutralized with DMEM-10% FBS and thecells are centrifuged. The pellet of dissociated cells is resuspended in15 ml of medium with 0.02% BSA at the density of 0.66×10⁶ cells per ml(maximum) and transferred to Petri dish (about 6.6 million of cells/10ml/dish of 100 mm).

The cell suspension is incubated in the Thy 1.1 coated Petri dish during45 min at 37° C. with gentle agitation every 15 min to preventnon-specific binding. The majority of fibroblast cells expressing Thy1.1adhere on the dish. At the end of the incubation, the cell suspension isrecovered and centrifuged. This cell suspension contains in theory onlySchwann cells. Cells are centrifuged and cell pellet is suspended ingrowth medium with 10 μM of Forskolin at 16 000 cells/cm² in T75 cm²flask Poly-L-Lysine treated.

1.3 Quantitative Reverse Transcriptase Polymerase Chain Reaction(Q-RT-PCR)

Quantitative RT-PCR is used to compare the levels of PMP22 mRNA afterdrug stimulation, relative with housekeeping Ribosomal L13A mRNA in ratSchwann cell primary culture.

After rinsing with cold sterilized PBS, total RNAs from each cell sampleare extracted and purified from SC using the Qiagen RNeasy micro kit(Qiagen #74004). Nucleic acids are quantified by Nanodropspectrophotometer using 1 μl of RNA sample. The RNA integrity isdetermined through a BioAnalyzer (Agilent) apparatus.

RNAs are reverse-transcribed into cDNA according to standard protocol.cDNA templates for PCR amplification are synthesized from 200 ng oftotal RNA using SuperScript II reverse-transcriptase (Invitrogen #18064-014) for 60 min at 42° C. in the presence of oligo(dT), in a finalvolume of 20 μl.

cDNAs are subjected to PCR amplification using the «LightCycler® 480»system (Roche Molecular Systems Inc.) Each cDNA are diluted five timesbefore being used for PCR amplification. 2.5 μl of this cDNAs enters thePCR reaction solution (final volume of 10 μl). Preliminary experimentsensured that quantitation was done in the exponential phase of theamplification process for both sequences and that expression of thereference gene was uniform in the different culture conditions.

PCR reaction is performed by amplification of 500 nM of forward primerof rat PMP22 (NM_017037), 5-GGAAACGCGAATGAGGC-3 (SEQ ID NO: 1), and 500nM of reverse primer 5-GTTCTGTTTGGTTTGGCTT-3 (SEQ ID NO: 2)(amplification of 148-bp). A 152-bp fragment of the RPL13A ribosomal(NM_173340) RNA is amplified in parallel in separate reactions fornormalization of the results by using a 500 nM of forward primer5-CTGCCCTCAAGGTTGTG-3 (SEQ ID NO: 3), and a 500 nM of reverse primer5-CTTCTTCTTCCGGTAATGGAT-3 (SEQ ID NO: 4).

We used FRET chemistry to perform RT-Q-PCR analysis. FRET probes arecomposed of 0.3 μM of Pmp22-FL-5-GCTCTGAGCGTGCATAGGGTAC (SEQ ID NO: 5)or Rp113A-FL-5-TCGGGTGGAAGTACCAGCC (SEQ ID NO: 6), labelled at their 3′end with a donor fluorophore dye (Fluorescein). 0.15 μM Red640 probesare defined as follows: Pmp22-red-5′-AGGGAGGGAGGAAGGAAACCAGAAA (SEQ IDNO: 7) or Rp113A-red-5′-TGACAGCTACTCTGGAGGAGAAACGGAA (SEQ ID NO: 8),labelled at their 5′ end with an acceptor fluorophore dye (Rhodamine Red640).

Each PCR reaction contained 2.5 μl cDNA template in a final volume of 10μl of master mix kit (Roche #04-887301001).

The following PCR conditions are used: 10 sec at 95° C., 10 sec at 63°C. and 12 sec at 72° C. and 30 sec at 40° C. (Forty amplificationcycles). The relative levels of PMP22 gene expression is measured bydetermining the ratio between the products generated from the targetgene PMP22 and the endogenous internal standard RPL13A.

1.4 PMP22 Protein Expression Analysis by Flow Cytometry (FACS)

8 hrs, 24 hrs and 48 hrs after drugs incubation, supernatants arerecovered, centrifuged and frozen. SC are detached with trypsin-EDTA. Assoon as the majority of cells are in suspension, the trypsin isneutralised using DMEM with 10% FCS.

Supernatants with cells are recovered and centrifuged. The pellets ofcells are transferred in micro tubes, washed in PBS once and fixed witha specific solution (AbCys #Reagent A BUF09B). 10 minutes later, cellsare rinsed once with PBS and kept at 4° C.

Five days after cell fixation, all cell preparations with differentincubation times are labelled using the following protocol.

Cells are centrifuged at 7000 rpm for 5 minutes and the pellets aresuspended in a solution of permeabilization (AbCys #Reagent B BUF09B)and labelled with primary PMP22 antibody (Abcam #ab61220, 1/50) for 1 hrroom at temperature. Cells are then centrifuged at 7000 rpm for 5minutes and cell pellets are rinsed once in PBS. A secondary antibody isadded, coupled to Alexa Fluor 488 (goat anti-rabbit IgG, MolecularProbes #A11008, 1/100), for one hour at room temperature. Cells are thencentrifuged at 7000 rpm for 5 minutes and cell pellets are rinsed oncein PBS. The labelling is increased adding a tertiary antibody coupled toAlexa Fluor 488 (chicken anti-goat IgG, Molecular Probes #A21467, 1/100)for one hour incubation, at room temperature. Cells are then rinsed oncein PBS. Control without any antibody (unlabelled cells) is performed todetermine the level of autofluorescence and adapted the sensitivity ofthe photomultiplicators. Control with both secondary and tertiaryantibodies but without primary antibody, is performed to assess nonspecific binding of antibodies.

Data acquisition and analysis are performed with a FACS Array cytometerand FACS Array software (Becton Dickinson) on 5000 cells. ForwardScatter (FSC) correlated with cell volume (size) and Side Scatter (SSC)depending on inner complexity of cells (granularity) are analysed. Forexpression of PMP22, analysis is performed within the total cells andpercent of positive cells is calculated. Positive cells are cells withfluorescence intensity higher than the control with secondary antibody.

In order to quantify the number of SC, cells in control medium areanalysed using antibodies anti-S100 Protein.

Cells are prepared according to the following protocol: Schwann cellsare stained with antibody anti-S100 Protein (Dako #S0311, 1/100) for 1hr room at temperature. This antibody is labelled according to protocoldescribed above for PMP22 immunostaining but without incubation withtertiary antibody.

1.5. Drug Incubation and Activity

Drugs are incubated for 24 hrs or 48 hrs in the same defined medium thandescribed above (3 wells/condition) in absence of Forskolin to avoidadenylate cyclase stimulation saturation, but in presence of 10 nM ofprogesterone. After drug incubation, supernatants are recovered andSchwann cells are frozen for RT-Q-PCR analysis.

These experiments are summarized in Table 1.

TABLE 1 Combination PMP22 expression Mix1 down regulation Mix2 downregulation Mix3 down regulation Mix4 down regulation Mix5 downregulation Mix6 down regulation

2. Assessment of Synergistic Effect of Compounds in Mix7 in a Co-CultureModel for CMT

A model of co-culture was used as an in vitro model of CMT1A. This modelof myelination consists in co-culturing sensory neurons and Schwanncells from male PMP22 Transgenic (TG) dissociated Dorsal Root Ganglia(DRG).

The aim of this study is to assess the effect of 3 test compounds(+/−Baclofen, Naltrexone and Sorbitol) and Mix7 (a mixture of these 3drugs) on myelination process. The effect of the 3 test compounds, andtheir mixture on myelination, are assessed by evaluating Myelin BasicProtein (MBP) expression in presence of ascorbic acid.

2.1 Materials and Methods

15 days gestation pregnant female rats are killed by cervicaldislocation. The embryos are removed from the uterus and are at similarfetal stage of development.

2.1.1 Genotyping

A piece of each embryo head (3 mm³) is placed in a 2 ml tube DNase free.The DNA is extracted with the SYBR Green Extract-N-Amp tissue PCR kit(Sigma, ref XNATG-1KT). 120 μl of extraction solution (Kit Sigma, refXNATG-1KT) was put on each piece of embryo head. The heads are incubatedfor 10 min at room temperature. At the end of this incubation, the headsare incubated for 5 min at 95° C. in the extraction solution.Immediately after this last incubation, 100 μl of neutralizing solutionare added, each DNA extract is diluted at 1/40 with sterile ultrapurewater (Biosolve, ref: 91589) and stored at +4° C. until use. Thegenotyping of female (F) and male (M) embryos is performed during thedissection of the DRG, with the kit Fast SYBR Green Master Mix (AppliedBiosystem, 4385612). The gender of each embryo is determined using themale SRY gene. The SRY primers are supplied by Pharnext (SRY-F (SEQ IDNO:9): 5′-GAGAGAGGCACAAGTTGGC-3′; SRY-R (SEQ ID NO:10):5′-GCCTCCTGGAAAAAGGGCC-3′). SRY primers are diluted at 3 μM in sterileultrapure water (Biosolve, ref: 91589). A mix for PCR is prepared withultrapure water (4 μl per sample), primer at 3 μM (2 μl per sample) andMaster Mix (10 μl per sample). In a PCR 96 wells plate, 16 μl of PCR mixis deposited in each well. 4 μl of each diluted DNA is added accordingto a plan deposit. The PCR is run using the 7500 fast RT-PCR system(Applied Biosystem), with the following program:

Beginning: 95° C.—20 sec

45 cycles: 95° C.—10 sec, 65° C.—10 sec, 72° C.—30 sec (dataacquisition).

Melt curve: 95° C.—15 sec, 64° C.—1 min, 90° C.—30 sec (continuous dataacquisition), 60° C. 15 sec. The amplification plots and melt curves areanalyzed with the 7500 software (Applied Biosystems).

The results for each sample are compared to negative control (ultrapurewater) and to the positive control (TG/Male and WT/Female), to concludeon the genotype of each embryo.

2.1.2 Sensory Neurons and Schwann Cells Co-Cultures

Rat Dorsal root ganglions are cultured as previously described byCosgaya et al., 2002 and Rangaraju et al., 2008.

Each embryo is dispatched on numerating petri dish (35 mm of diameter).The head of embryo is cut, placed on 1.5 ml tube DNAase free; the ADN isextracted with the Extract-N-Amp Tissue Kit (Sigma Aldrich). Thegenotyping (Male (M) and female (F), wild type and PMP22 transgenic) isperformed with the kit Fast SYBR Green Master Mix (Applied Biosystem).This genotyping is performed in parallel of the dissection of dorsalroot ganglia (DRG), so that at the end of the dissection, only one typeof culture (DRG from transgenic male) is done. DRG of each embryo iscollected, placed in ice-cold medium of Leibovitz (L15, Invitrogen). Atthe end of the dissection, DRG of TGM are pooled and dissociated bytrypsinization (trypsin EDTA, 0.05%; Invitrogen) for 20 min at 37° C.The reaction is stopped by addition of DMEM containing 10% of fetalbovine serum (FBS) in the presence of DNAase I (Roche). The suspensionis triturated with a 10 ml pipette. Cells are then centrifuged at 350×gfor 10 min at room temperature. The pellet of dissociated cells isresuspended in neurobasal medium (Invitrogen) containing 2% of B27(Invitrogen), 1% of penicillin-streptomycin (Invitrogen), 1% de Lglutamine and 50 ng/ml NGF (Sigma). This medium is the neuronal medium.Viable cells are counted in a Neubauer cytometer using the trypan blueexclusion test (Sigma) and seeded on the basis of 10 000 cells per wellin 96 well-plates (Greiner) treated with poly-L-lysine. The plates aremaintained at 37° C. in a humidified incubator, in an atmosphere of air(95%)-CO2 (5%). Half of the standard neuronal culture medium is changedevery other day. The cultures are maintained in standard neurobasalmedium for 7 days to allow Schwann cells to populate the sensory neuronneurites. On day 7, the cultures are fed with standard neuronal mediumsupplemented or not with 50 μg/ml ascorbic acid in order to initiatebasal lamina formation and myelination.

2.1.3. Drug Incubation

On day 7, the following test compounds (alone or in combination) areadded in the medium with 50 μg/ml ascorbic acid:

-   -   (RS)-Baclofen    -   Natrexone    -   d-Sorbitol    -   Mix7=the combination of the 3 individual compounds.

These compounds or compound combination are tested at the followingconcentrations (Table 2):

TABLE 2 Concentration of individual drugs or in combination used for invitro studies of MBP expression in TG DRG/SC co-cultures. Dose 1 Dose 2Dose 3 Dose 4 Dose 5 Dose 6 Dose 7 Individual Naltrexone 5 μM 1 μM 200nM 40 nM 8 nM 1.6 nM 320 pM drugs d-Sorbitol 500 μM 100 μM 20 μM 4 μM800 nM 160 nM 32 nM (RS)-Baclofen 5 μM 1 μM 200 nM 40 nM 8 nM 1.6 nM 320pM Mix7 Naltrexone 5 μM 1 μM 200 nM 40 nM 8 nM 1.6 nM 320 pM d-Sorbitol500 μM 100 μM 20 μM 4 μM 800 nM 160 nM 32 nM (RS)-Baclofen 5 μM 1 μM 200nM 40 nM 8 nM 1.6 nM 320 pM

The test compounds are incubated for 5 different times: 5, 9, 10, 11 and13 days.

Three separate and independent cultures of DRG (from TG embryos malerats) are done. These conditions are assessed in presence of ascorbicacid, 6 wells per condition. The solution ready to use of all testcompounds are extemporaneously prepared from a stock solution, stored at−20° C. This solution is prepared once a week. Half of the standardneuronal medium supplemented with test compounds and ascorbic acid (eachat the concentration 1×) are changed every other day.

2.1.4 Staining Protocol

After 5, 9, 10, 11 and 13 days of incubation, cells are fixed by a coldsolution of ethanol (95%) and acetic acid (5%) for 10 min. The cells arepermeabilized and blocked with PBS containing 0.1% saponin and 10% goatserum for 15 min. Then, the cells are incubated with a specific markerof myelin: polyclonal antibody anti-myelin basic protein (MBP) antibody(Sigma 118K0431).

This antibody is revealed with Alexa Fluor 568 goat anti-rabbit IgG andAlexa Fluor 488 goat anti-mouse IgG (Molecular probe 687621, 623962).Nuclei of neurons are labeled by a fluorescent marker (Hoechst solution,SIGMA ref B1155).

2.1.5. Data Processing

Per well, 20 pictures are taken using InCell Analyzer™ 1000 (GEHealthcare) with 20× magnification. All images are taken in the sameconditions. Analysis of total length of myelinated axons wasautomatically done (length and area around axons) using Developersoftware (GE Healthcare). All values will be expressed asmean+/−s.e.mean. Statistic analyses are done on different conditions(ANOVA followed by Fisher's PLSD test when allowed).

2.2. Results Synergistic Effect of Drugs in the Efficacy of Mix7

An important synergistic effect of drugs composing the Mix7 combinationis observed on MBP expression. Indeed, on day 10 (=17 days of culture),combination of (RS)-Baclofen, Naltrexone and d-Sorbitol significantlyincreases MBP expression at doses 1 and 6 as shown in FIGS. 1A and 2A.By contrast, the above drugs used individually have no substantialeffect compared to control (FIGS. 1B-D and 2B-D).

A significant effect on MBP expression is also recorded after 10 days ofincubation at doses 2, 3, 4, 5 and 7 of Mix7 (FIG. 3A).

This effect is still observed on day 11 with doses 2-7 (FIG. 3B) in formof a clear bell shape curve.

C. Experiments In Vivo in CMT Animal Model

We tested the compounds for therapeutic effect in a rat model.

The experimental groups are formed with young rats of both gendersseparately. The rats are assigned to the groups following randomizationschedule based on the body weight. In some experiments the randomizationis based on the performances of the rats in the bar test. Both gendersare represented by separate control groups that are numerically equal orbigger than the treatment groups.

The rats are treated chronically with drugs—force fed or injected byAlzet osmotic subcutaneous pump (DURECT Corporation Cupertino, Calif.),depending on each drug bioavailability during 3 or 6 weeks. In all thein vivo experiments performed, the Mix7 is administered by gavage.

The animals are weighted twice a week in order to adjust the doses togrowing body weight. If the osmotic pump is chosen for the treatmentadministration, the doses of the drug are calculated on the basis of theestimated mean body weight of the animals expected for their age overthe period of the pump duration (6 weeks). The pumps are re-implanted ifnecessary, with the appropriated anesthesia protocol.

Behavioural Tests

Each three or four weeks the animals are subjected to a behaviouraltest. Each test is conducted by the same investigator in the same roomand at the same time of the day; this homogeneity is maintainedthroughout entire experiment. All treatments and genotype determinationare blinded for the investigator. “Bar test” and “Grip strength” hasbeen mainly used to access the performance throughout study. Theschedule of the bar test may change as the animal growth (in order toavoid the bias due to the learning, for example).

The assay of the grip strength allows detection of subtle differences inthe grip performance that seems to be composed of the muscle force,sensitivity status (for instance, painful tactile feelings may changemeasured values of the force), behavioural component (“motivation”). Thevalues differ between fore and hind limbs and greatly depend on the ageof the animals.

The grip strength test measures the strength with which an animal holdson to a grip with its forepaws or its hindpaws separately. A dynamometeris placed with a grip to measure the strength (Force Gauge FG-5000A).The rat is held by the experimenter in a way that it grasps the gripeither with its forepaws or with its hind paws and pulls gently the ratbackwards until it releases the grip. The force measured when the animalreleases the grip is recorded.

Two successive trials measuring the forepaws and two successive trialsmeasuring the hindpaws strength per animal are processed; only themaximum score (one for forepaws and one for hindpaws) is noticed (in N).

The Bar Test

The bar test evaluates rats' ability to hold on a fix rod. Pmp22 ratswhich display muscular weakness, exhibit a performance deficit in thistest (Sereda et al, 1996). The rat is placed on its four paws on themiddle of the rod (diameter: 2.5 cm; length: 50 cm; 30 cm above thetable). Trials are performed consecutively; the number and the durationof trials in our experiments have been depending on batches of theanimals. This variability in the testing has been introduced in order todetermine the schedule appropriated to the best detection of the motordeficiency in the CMT rats in the course of the experiments.

Performance indices are recorded on each session:

-   -   The number of trials needed to hold for 60 sec (or 30 sec for        batch 1, session 1 and 2) on the rod.    -   The time spent on the bar (i.e. the fall latency) in each trial        and the average on the session. In the experimental procedures        where the session ends after the rat has stayed for a cut-off        time, i.e. 30 or 60 s, on the bar, a performance of the cut-off        time (30 s or 60 s) is assigned to trials not completed (eg: for        batch 8, for an animal which stays on the bar less than 10 sec        on trials 1, 2 and 3, then for 60 sec on trials 4 and 5, 60 s is        assigned to trials 6 to 10).    -   The number of falls.

General Health Assessment

Body weights, overt signs (coat appearance, body posture, gait, tremoretc.) of the animals are monitored throughout the experiment. The ratingscale is used for recording: 0=normal, 1=abnormal.

The Gait

Each rat is observed in a novel rat cage (dimensions 55×33×18 cm)without litter for five minutes. The gait of rats is evaluated with 4parameters:

-   -   Score 0: normal gait (fluid)    -   Score 1: abnormal gait (not fluid or the rat has a slight limp)    -   Score 2: moderate incapacity (the rat drags one's leg and is        able to put it right and walk)    -   Score 3: serious incapacity (the rat drags its one's or both        hindpaws but is unable to put it/them right).

Inclined Plane Test

The sliding apparatus had a 30×50 cm Plexiglas plane that could beinclined at an angle of 0° (horizontal) to 60°. Each rat was initiallyplaced on the 25°-angled inclined plane in the up-headed position(head-up orientation); two trials separated by 1 min are performed. 30min later, the same experiment is realized on a 35°-angled inclinedplane then on 40°-angled inclined plane. During this time the rat wasreturned to its cage. The plane is cleaned after each trial.

The performances of rats are evaluated by 4 different scores:

-   -   Score 0: no slide    -   Score 1: a little slide (one or two paws)    -   Score 2: a moderate slide (4 paws) but not until the end of the        plane    -   Score 3: the rat is sliding until the very bottom of the plane.

Further Tests

When appropriate, the rats are subjected to electrophysiologicalevaluation, histological measurement and the pmp22 RNA expression levelin the sciatic nerve is quantified.

Quantification of pmp22 RNA in Sciatic Nerve by Quantitative RT-PCR

Total RNA was isolated from left sciatic nerves using Qiazol (ref No79306, Qiagen Gmbh, Germany) followed by the single-step purificationmethod with RNeasy Mini Kit (ref No 74106, Qiagen Gmbh, Germany)described by the manufacturer's protocol (Qiagen-RNeasy Fibrous tissueHandbook). DNA contamination was removed by digestion with RNase-freeDNase I by use of the DNA-free kit (Qiagen-Rnase-free dnase set 1500Kunits, ref No 1023460).

RNA concentrations are estimated by NanoDrop ND-1000 and a test ofquality control was done by Agilent RNA 6000 nano chips on Agilent 2100Bioanalyzer.

Reverse transcription and real-time PCR: Quantitative RT-PCR (RT-Q-PCR)was performed as follows: 80 ng of total RNA was reverse transcribedusing SuperScript™ II Reverse Transcriptase (Invitrogen, Carlsbad,Calif.) with Oligo(dT)12-18 (Invitrogen, Carlsbad, Calif.) in a 20-μlreaction volume.

Real-time PCR was performed with a rapid thermal cycler system(LightCycler® 480 II, 384-Well, Roche, Switzerland). Amplifications areperformed in a 10 μl total volume with primers concentration optimizedbetween 130 nM and 1 μM. Primers and template are supplemented withLightCycler® 480 SYBR Green I Master (2× conc. Roche, Cat. Ref No 04 887352 001). Nucleotides, MgCL₂, Taq DNA polymerase and buffer are includedin the mix. An amplification protocol incorporated an initial incubationat 95° C. for 10 min for the activation of Taq DNA polymerase followedby 45 cycles, with a 95° C. denaturation for 10 s, 60° C. annealing for40 s and 72° C. extension for 10 s (detection of the fluorescent productwas performed at the end of the 72° C. extension period by a singleacquisition mode) and ended by a cycle of melting curve with 95° C.denaturation for 5 s, 63° C. annealing for 60 s and 95° C. (from 63° C.to 95° C. the ramp rate is 0.11° C./s and detection of the fluorescentproduct was continuous). To confirm the amplification specificity, thePCR product from each primer pair was subjected to a melting curveanalysis. Relative quantification was performed based on the crossingpoint (Cp value) for each of the PCR samples. The point at which thefluorescence of a sample rises above the background fluorescence iscalled the “crossing point (Cp) of the sample. Rattus norvegicus MyelinProtein Zero (MPZ) gene was used for normalization (Sereda et al, 2006).The sequences of the primers (synthesized by Eurofins MWG Operon,Germany) used for the RT-Q-PCR analysis are:

PMP22-forward: (SEQ ID NO: 11) 5′-TGTACCACATCCGCCTTGG-3′ andPMP22-reverse: (SEQ ID NO: 12) 5′-GAGCTGGCAGAAGAACAGGAAC-3′.MPZ-forward: (SEQ ID NO: 13) 5′-TGTTGCTGCTGTTGCTCTTC-3′ and MPZ-reverse:(SEQ ID NO: 14) 5′-TTGTGAAATTTCCCCTTCTCC-3′.

Results

Mix1 composition improves bar test performances throughout the treatmentprocedure (FIG. 4).

Mix1 improves the gait score of transgenic rats after 3 and 6 weeks oftreatment as shown in FIG. 5.

Mix1 increases the performances of transgenic rats after 3, 6, 9 and 12weeks of treatment in the inclined plane test at 25° described in theFIG. 6.

FIG. 7 illustrates the positive effect of Mix2 on gait score oftransgenic rats at 25, 35 and 40° in the inclined plane test.

Mix7 (dose 3) significantly decreases the pmp22 RNA gene expression inthe sciatic nerve of pmp22 transgenic rats (FIG. 9).

The performances of pmp22 rats treated with Mix7 (dose 2 and dose 3) areimproved in the inclined plane test at 35° (FIG. 10). More specifically,29 and 33% of rats belong to the good performance group, compared to 5%for TG placebo group, and 29 and 11% of rats belong to the poorperformance group compared to 60% for the TG placebo group. P-value(versus the TG placebo) is equal to 0.0152 for the TG rats treated withMix7-dose 2 and p-value is equal to 0.002 for the TG rats treated withMix7-dose 3 versus the TG placebo).

Mix7-dose 3 significantly increases the fall latency time of pmp22 ratsin bar test after 9 weeks of treatment (FIG. 11): black dashed line,p=4.56·10−2, n=18. Significant difference between TG placebo rats (blackplain line, n=20) and WT placebo rats (grey plain line, p=3.82·10−7,n=18) is also observed.

The FIG. 12 illustrates the improvement of grip strength of the pmp22rats treated with the Mix7-dose 3.

The FIG. 13 shows the significant correlation between the bar testlatency time (after 9 weeks of treatment with the Mix7-dose 3) and theexpression level of pmp22 RNA.

The FIG. 14 displays the significant correlation between the bar testlatency time after 9 weeks of treatment with Mix7-dose 3 and theconduction velocity of the sensitive nerve (tail).

Similar results are obtained for other combinations (see Table 3).

TABLE 3 Combination PMP22 rat disease phenotype Mix1 improvement Mix2improvement Mix3 improvement Mix4 improvement Mix5 improvement Mix6improvement

These data show that, in vivo, the combinations and regimens of thisinvention allow effective treatment of CMT.

D. In Vivo Effect in a Model of Toxic Neuropathy

The drug treatments or regimens are orally administered from the daybefore the first intraperitoneal injection of Oxaliplatin 3 mg/kg (D-1)until the day before the last testing day (D16). Animals belonging tothe Oxaliplatin-treated group are dosed daily with distilled water (10ml/kg). Animals are dosed with the tested treatment and distilled waterdaily during the morning whereas Oxaliplatin is administered on theafternoon.

During the testing days (i.e. D1, D4, D10), the treatment and distilledwater are administered after the test. Regarding the testing day (D4),including compounds and vehicle administrations and Oxaliplatininjection, the treatment and distilled water are administered prior tothe injection of Oxaliplatin after the test. Animals from thereference-treated group are dosed only during the testing days (i.e. D1,D4, D10 and D17).

Cold allodynia is assessed by measuring the responses to thermalnon-nociceptive stimulation (acetone test) on D1 (around 24 h after thefirst injection of Oxaliplatin 3 mg/kg (acute effect of Oxaliplatin), onD4, D10 and (chronic effect of Oxaliplatin) and on D17 (residual effectof Oxaliplatin one week after completion of treatment).

Testing is done using the acetone test 2 h post-administration of thereference. The reference substance is Gabapentin, 100 mg/kg, per os(once a day×4 testing days).

Acetone Test

Cold allodynia is assessed using the acetone test. In this test, latencyof hindpaw withdrawal is measured after application of a drop of acetoneto the plantar surface of both hindpaws (reaction time) and theintensity of the response is scored (cold score).

Reaction time to the cooling effect of acetone is measured within 20 sec(cut-off) after acetone application. Responses to acetone are alsograded to the following 4-point scale: 0 (no response); 1 (quickwithdrawal, flick of the paw); 2 (prolonged withdrawal or markedflicking of the paw); 3 (repeated flicking of the paw with licking orbiting).

Six trials by rat are performed. For each experimental group, theresults are expressed as the cumulative cold score defined as the sum ofthe 6 scores for each rat together±SEM. The minimum score being 0 (noresponse to any of the 6 trials) and the maximum possible score being 18(repeated flicking and licking or biting of paws on each of the sixtrials).

Gabapentin source: Zhejiang Chiral Medicine Chemicals, China

Oxaliplatin source: Sigma, France

The results are depicted on FIG. 8. They clearly show a protectiveeffect of the composition of this invention on oxaliplatin-inducedneuropathy.

E. In Vivo Effect in a Model of ALS Animal Model

We have chosen the SOD1^(G93A) rat model (generated by Howland et al) tomimic the Amyotrophic Lateral Sclerosis pathology. This modeloverexpresses the mutated SOD1 gene in spinal cord, many brain regionsas well as peripheral tissues. The onset of the motor neuron disease ofthis model is about at 115 days; it appears as hind limb abnormal gait.In few days, the paralysis of hind limb arises.

Experimental Procedures

We obtained colonies by crossing breeder SOD1^(G93A) rats with SpragueDawley female rats. Heterozygous SOD1^(G93A) rats are identified withpolymerase chain reaction (PCR) of tail DNA with primers specific forhSOD1 [1]. Animals are maintained in a room with controlled illumination(lights on 0500-1900 h) and temperature (23±1° C.), and given freeaccess to food and water. All the animal procedures in the present studyare carried out in accordance with the guidelines standards of animalcare.

Body weight measurement was performed every week and behavioural testsbegan at an age of 60 days and continued until endpoint. The treatmentsae administered every day per oral or subcutaneous way from the age of 5weeks.

1. Observation Test: Characterization of the General Aspect

Each rat was observed in a novel rat cage (dimensions 55×33×18 cm)without litter for five minutes. 5 different parameters are recorded:

The Gait

-   -   score 0: normal gait (fluid)    -   score 1: abnormal gait (not fluid or the rat has a slight limp)    -   score 2: moderate incapacity (the rat drags one's leg and is        able to put it right and walk)    -   score 3: serious incapacity (the rat drags its one's or both        hindpaws but is unable to put it/them right)

The Coat Aspect

-   -   score 0: clean and silky coat    -   score 1: piloerection or dirty coat

The Tremor

-   -   score 0: no tremor    -   score 1: tremor

The Body Position

-   -   score 0: normal    -   score 1: abnormal (flattened or archering its back)

The Hindpaws Position

-   -   score 0: normal    -   score 1: spread hindpaws

2. The Motor Score Test: Characterization of the Motor Deficit

This test evaluates the ability of rats to right themselves within 30sec of being turned on either side (righting reflex) (Gale et al).

A non-parametrical scoring system was used following these criteria(Matsumoto et al, Thonhoff et al):

-   -   score 0: the rat is unable to right itself from either side        within 30 sec    -   score 1: the rat is unable to right itself from only one side        within 30 sec    -   score 2: the rat is able to right itself from both sides within        30 sec but is unable to stand in the cage; it is always dragging        some parts of body    -   score 3: the rat is able to right itself from both sides within        30 sec, is unable to stand in the cage but is not dragging some        parts of body    -   score 4: the rat is able to right itself from both sides within        30 sec, is able to stand in the cage but has visible functional        deficits    -   score 5: the rat is able to right itself from both sides within        30 sec, is able to stand in the cage and no visible functional        deficits.

The end-point of disease is fixed at score 0; the rat is theneuthanized.

3. Inclined Plane Test: Characterization of the Motor Deficit

The sliding apparatus had a 30×50 cm plexiglas plane that could beinclined at an angle of 0° (horizontal) to 60°. Each rat was initiallyplaced on the 25°-angled inclined plane in the up-headed position(head-up orientation); two trials separated by 1 min are performed. 30min later, the same experiment is realized on a 35°-angled inclinedplane then on 40°-angled inclined plane. During this time the rat wasreturned to its cage. The plane is cleaned after each trial.

The performances of rats are evaluated by 4 different scores:

-   -   score 0: no slide    -   score 1: a little slide (one or two paws)    -   score 2: a moderate slide (4 paws) but not until the end of the        plane    -   score 3: the rat is sliding until the very bottom of the plane.

4. The Wire Mesh Test: Characterization of the Motor Ability inDifficult Situation

A wire mesh was placed in contact with a box at the top (at an angle of70°) and the edge of a table at the bottom. Each rat was placed on thebottom of the wire mesh and motivated to ascend by placing theirlittermates in the box at the top. Each rat was trained once a week (3trials).

The recorded parameter was the latency time to reach the top of the wiremesh.

5. The Open Field Test: Characterization of the Locomotor Activity

The locomotor activity was measured in a Plexiglas box (45×45×30 cm,Acti-Track by BIOSEB, Lyon, France) with 16 photo-cell beams followingthe two axes, 1 and 5 cm above the floor.

The spontaneous and exploratory activity of each rat was evaluatedduring 3 hours.

4 parameters are recorded (the total travelled distance, the number ofrearings, the percentage of travelled distance and of time spent in thecenter of the openfield).

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1-13. (canceled)
 14. A pharmaceutical composition comprising, as activeingredients: (i) baclofen or a pharmaceutically acceptable salt thereofin an amount between about 1 to about 300 μg/kg of a human subject, (ii)sorbitol or a pharmaceutically acceptable salt thereof, and (iii)naltrexone or a pharmaceutically acceptable salt thereof in an amountbetween about 1 to about 100 μg/kg of the human subject; and apharmaceutically suitable excipient or carrier.
 15. The compositionaccording to claim 14, wherein said composition comprises baclofen or apharmaceutically acceptable salt thereof in an amount between about 10and about 200 μg/kg of the human subject.
 16. The composition accordingto claim 14, wherein said composition comprises naltrexone or apharmaceutically acceptable salt thereof in an amount between about 1and about 50 μg/kg of the human subject.
 17. The composition accordingto claim 14, wherein said composition comprises baclofen or apharmaceutically acceptable salt thereof in an amount from between about10 and about 200 μg/kg of the human subject and naltrexone or apharmaceutically acceptable salt thereof in an amount from between about1 and about 50 μg/kg of the human subject.
 18. The composition accordingto claim 14, wherein the baclofen or a pharmaceutically acceptable saltthereof, sorbitol or a pharmaceutically acceptable salt thereof, andnaltrexone or a pharmaceutically acceptable salt thereof are present inan amount effective to treat Charcot-Marie Tooth Disease Type 1A (CMT1A)in the human subject when administered once, twice, or three times dailyto the human subject.
 19. The composition according to claim 14, whereinthe sorbitol or a pharmaceutically acceptable salt thereof isD-sorbitol.
 20. The composition according to claim 14, wherein thebaclofen or a pharmaceutically acceptable salt thereof is RS baclofen.21. The composition according to claim 14, wherein the baclofen or apharmaceutically acceptable salt thereof is RS baclofen and the sorbitolor a pharmaceutically acceptable salt thereof is D-sorbitol.
 22. Thecomposition according to claim 14, wherein the composition contains noadditional active agents.
 23. The composition according to claim 14,wherein the composition is formulated for oral administration.
 24. Thecomposition according to claim 14, wherein the composition is a liquidformulation.
 25. The composition according to claim 14, wherein thecomposition is a liquid formulated for oral administration.
 26. A unitdosage form comprising: (i) baclofen or a pharmaceutically acceptablesalt thereof in an amount between about 1 and about 300 μg/kg of a humansubject, (ii) sorbitol or a pharmaceutically acceptable salt thereof,and (iii) naltrexone or a pharmaceutically acceptable salt thereof in anamount between about 1 and about 100 μg/kg of the human subject; and apharmaceutically acceptable excipient or carrier.
 27. The unit dosageform according to claim 26, comprising baclofen or a pharmaceuticallyacceptable salt thereof in an amount between 10 and 200 μg/kg of thehuman subject and naltrexone or a pharmaceutically acceptable saltthereof in an amount between 1 and 50 μg/kg of the human subject. 28.The unit dosage form according to claim 26, wherein the baclofen or apharmaceutically acceptable salt thereof, sorbitol or a pharmaceuticallyacceptable salt thereof, and naltrexone or a pharmaceutically acceptablesalt thereof are present in an amount effective to treatCharcot-Marie-Tooth Disease Type 1A (CMT1A) in the human subject whenadministered once, twice, or three times daily to the human subject. 29.The unit dosage form according to claim 26, wherein the baclofen or apharmaceutically acceptable salt thereof is RS baclofen and the sorbitolor a pharmaceutically acceptable salt thereof is D-sorbitol.
 30. Theunit dosage form according to claim 26, wherein the unit dosage formcontains no additional active agents.
 31. The unit dosage form accordingto claim 26, wherein the unit dosage form is a liquid formulated fororal administration.
 32. A patient pack comprising a liquid formulationfor oral administration, comprising a composition comprising: (i)baclofen or a pharmaceutically acceptable salt thereof in an amountbetween about 1 and about 300 μg/kg of a human subject, (ii) sorbitol ora pharmaceutically acceptable salt thereof, and (iii) naltrexone or apharmaceutically acceptable salt thereof in an amount between about 1and about 100 μg/kg of the human subject; a pharmaceutically acceptableexcipient or carrier; and, optionally, instructions for administrationof the liquid formulation;
 33. The patient pack according to claim 32,comprising baclofen or a pharmaceutically acceptable salt thereof in anamount between about 10 and about 200 μg/kg of the human subject andnaltrexone or a pharmaceutically acceptable salt thereof in an amountbetween about 1 and about 50 μg/kg of the human subject.
 34. The patientpack according to claim 32, wherein the baclofen or a pharmaceuticallyacceptable salt thereof, sorbitol or a pharmaceutically acceptable saltthereof, and naltrexone or a pharmaceutically acceptable salt thereofare present in an amount effective to treat Charcot-Marie Tooth DiseaseType 1A (CMT1A) in the human subject when the composition isadministered once, twice, or three times daily to the human subject. 35.The patient pack according to claim 32, wherein the liquid formulationcomprises divided doses.
 36. The patient pack according to claim 32,wherein each of the divided doses comprises baclofen or apharmaceutically acceptable salt thereof in an amount between about 1and about 300 μg/kg of a human subject and naltrexone or apharmaceutically acceptable salt thereof in an amount between about 1and about 100 μg/kg of the human subject.
 37. The patient pack accordingto claim 32, wherein each of the divided doses comprises baclofen or apharmaceutically acceptable salt thereof in an amount between about 10and about 200 μg/kg of a human subject and naltrexone or apharmaceutically acceptable salt thereof in an amount between about 1and about 50 μg/kg of the human subject.
 38. The patient pack accordingto claim 32, wherein the baclofen or a pharmaceutically acceptable saltthereof is RS baclofen and the sorbitol or a pharmaceutically acceptablesalt thereof is D-sorbitol.